1. Technical Field
The present disclosure relates to a multiple camera video surveillance system, in particular, to a correction method for errors in linking objects from multiple video sequences in a multiple camera video surveillance system and a multiple camera video surveillance system using the same.
2. Description of Related Art
A conventional video surveillance system provides specific object detection service for a single surveillance region, meanwhile sending the related video information and detection results back to a central server. However, the application of video surveillance methods for providing specific object detection service for a single surveillance region has been unable to satisfy all needs. For example, the application of post video analysis in practice often requires one to provide full descriptions including time and position trace related to people, events and objects within the overall surveillance system coverage to completely describe an incident. Consequently, specific event detection service for a specific environment has not been able to enable post video analysis. Therefore, multiple camera video surveillance systems have become the mainstream in current video surveillance systems.
Most modern multiple camera surveillance systems forward the video captured by each camera located in their specific surveillance region back to the central server. The central server further analyzes the video associated with each camera to obtain analysis results of objects in a single video sequence. Afterward, the central server obtains the temporal and spatial relations among objects in each corresponding video sequence (i.e., the positions and order of occurrence associated with each object in the corresponding surveillance region) and links a specific object according to the temporal relation among all discovered objects to obtain the trace information and the historical video sequence associated with the specific object in the overall multiple camera video surveillance environment.
Please refer to the U.S. Pat. No. 7,242,423 having the invention name of “Linking zones for object tracking and camera handoff”. The invention discloses a multiple camera video surveillance system that can analyze the video information captured by each camera independently so as to obtain the analysis for the detection and tracking result associated with each object in the surveillance range of a single video camera. Furthermore, the described video surveillance system extracts the relation between the locations of appearing and leaving objects and the corresponding time point thereof associated with each object in the surveillance range of each video camera based on the analysis result. Subsequently, a probability distribution function is established according to the relation between the locations of appearing and leaving objects and the corresponding time point thereof. Consequently, the described video camera surveillance system can predict the relations among the objects appearing in each video sequence using the above described probability distribution function so as to link a specific object in each video sequence to acquire the historical video image and the trace information associated with the specific object in the overall multiple camera video surveillance environment.
Moreover, please refer to the TW patent application No. 200943963 entitled “Integrated image surveillance system and manufacturing method thereof”. This application illustrates an image registration method that registers multiple video sequences captured by multiple video cameras, respectively, into a single video sequence to reduce the monitoring load of the user. Even though registering multiple video sequences of multiple video cameras into a single video sequence may effectively reduce the monitoring load of the user, this patent application has not disclosed a corresponding intelligent multiple camera video surveillance content analysis system to aid the user. In addition, because the size of the registered single video sequence is large, it could cause a high computation load on an intelligent multiple camera video surveillance content analysis system.
The aforementioned multiple camera video surveillance systems extract the trace images of each specific object based on the adopted algorithms of video analysis and object linking, automatically linking the identical specific objects from each captured video sequence. However, the actual environment may be different to the assumption of the adopted algorithms, and each method can generate different degrees of errors. Consequently, the aforementioned multiple camera video surveillance systems may mislink different objects and be unable to perform correction in an efficient manner.